Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
Critically Endangered | Endangered | Vulnerable |
---|---|---|
- | - | A3cd+4cd |
Year | Category | Criteria |
---|---|---|
2020 | Vulnerable | A3cd+4cd |
2018 | Vulnerable | A3cd+4cd |
2016 | Near Threatened | A2cd+3cd+4cd; C1 |
2013 | Near Threatened | A2cd+3cd+4cd; C1 |
2012 | Near Threatened | A2cd+3cd+4cd;C1 |
2008 | Near Threatened | A2c,d; A3c,d; A4c,d; C1 |
2004 | Near Threatened | |
2000 | Lower Risk/Near Threatened | |
1994 | Lower Risk/Least Concern | |
1988 | Lower Risk/Least Concern |
Migratory status | not a migrant | Forest dependency | high |
Land-mass type |
continent shelf island |
Average mass | - |
Estimate | Data quality | |
---|---|---|
Extent of Occurrence (breeding/resident) | 10,300,000 km2 | medium |
Severely fragmented? | no | - |
Estimate | Data quality | Derivation | Year of estimate | |
---|---|---|---|---|
Population size | 13000-27000 mature individuals | poor | inferred | - |
Population trend | decreasing | medium | suspected | 1989-2043 |
Rate of change over the future 10 years/3 generations (longer of the two periods) | 30-39% | - | - | - |
Rate of change over the past & future 10 years/3 generations (longer of the two periods) | 30-39% | - | - | - |
Generation length | 18.3 years | - | - | - |
Population justification: The population density of the Great Hornbill has been estimated from across several sites in its range. In Arunachal Pradesh in north-east India, the density of Great Hornbill in Namdapha Tiger Reserve was estimated to be around 4 birds per km2 (Naniwadekar and Datta, 2013) in the non-breeding season and this was similar in Pakke Tiger Reserve at 3.8 birds per km2 (Datta et al. unpublished data 2014). In Pakke Tiger Reserve, its overall density was estimated to be around 12 birds per km2 in an earlier study (Dasgupta and Hilaluddin, 2012). The density was estimated to be 1 bird per km2 in forests outside Namdapha Tiger Reserve (Naniwadekar et al. 2015a). In the rainforest fragments, the densities ranged from 3.4 to 10 birds per km2 (Raman & Mudappa, 2003). The density of Great Hornbill ranged between 1.5-4.4 individuals/km2 in Anamalai and Parambikulam Tiger Reserves, 0-4 individuals per km2 in Reserved Forests of Vazhachal-Sholayar and Malayattur and 0.6-4.5 individuals per km2 in rainforest fragments in Anamalai Hills (Mudappa & Raman, 2009). Densities are higher in Anamalai Tiger Reserve (~4 birds/ km2) as opposed to the adjoining shade coffee plantations (~2 birds/ km2) based on line-transect surveys between January 2017 and April 2018 (Pawar et al. unpublished data).
In Thailand, its population density has been estimated to range between 1.3-4.7 birds per km2 in Huai Kha Khaeng Wildlife Sanctuary, Thung Yai Naresuan Wildlife Sanctuary, Khao Yai National Park, and Budo Sangai Padi National Park. It ranges between 0.04-1.1 birds per km2 in nine other forest complexes in Thailand (Gale and Thongaree 2006, Jornburom et al. 2010, Poonswad et al. 2013).
These population densities indicate that the population within these sites, given the approximate habitat that lies within a suitable elevation range, can be estimated on a precautionary basis at 23,000 - 71,000 individuals. This is placed in the band 20 - 49,999 individuals, roughly equating to 13,000 - 27,000 mature individuals. Outside protected areas, even if adjacent, population densities can be considerably lower, often well below 1 individual per km2 (Gale and Thongaree 2006, Mudappa and Raman 2009, Naniwadekar et al. 2015), and it has been driven to local extinction across several sites both inside and outside Protected Areas in Arunachal Pradesh (Datta 2002, Naniwadekar et al. 2015a).
Trend justification: An analysis of deforestation between 2000 and 2012 estimated forest loss within the species's range at 26.1% over three generation lengths (55.2 years) (Tracewski et al. 2016). The species is generally intolerant of forest disturbance and additionally severely threatened by hunting. Thus, its actual rate of population decline is likely greater than the estimate decline based on forest loss alone. The rate of decline is tentatively placed in the band 30-49% over three generations. Since this species has a long generation length, with three generations stretching over 55 years, there is insufficient evidence to calculate the magnitude of reduction over the past three generations. Assuming the recent rate of decline remains constant, the species is projected to decline by 30-49% over the next three generations.
Country/Territory | Presence | Origin | Resident | Breeding visitor | Non-breeding visitor | Passage migrant |
---|---|---|---|---|---|---|
Bangladesh | extant | native | yes | |||
Bhutan | extant | native | yes | |||
Cambodia | extant | native | yes | |||
China (mainland) | extant | native | yes | |||
India | extant | native | yes | |||
Indonesia | extant | native | yes | |||
Laos | extant | native | yes | |||
Malaysia | extant | native | yes | |||
Myanmar | extant | native | yes | |||
Nepal | extant | native | yes | |||
Thailand | extant | native | yes | |||
Vietnam | extant | native | yes |
Country/Territory | IBA Name |
---|---|
Cambodia | Central Cardamoms |
Cambodia | Phnom Aural |
Cambodia | Phnom Bokor |
Cambodia | Phnom Samkos |
Nepal | Barandabhar forests and wetlands |
Nepal | Bardia National Park |
Nepal | Chitwan National Park |
Nepal | Mai Valley forests |
Nepal | Parsa Wildlife Reserve |
Vietnam | Ea So |
Vietnam | Kon Cha Rang |
Vietnam | Yok Don |
Habitat (level 1) | Habitat (level 2) | Importance | Occurrence |
---|---|---|---|
Artificial/Terrestrial | Plantations | major | resident |
Artificial/Terrestrial | Rural Gardens | major | resident |
Forest | Subtropical/Tropical Moist Lowland | major | resident |
Forest | Subtropical/Tropical Moist Montane | major | resident |
Altitude | 0 - 2000 m | Occasional altitudinal limits |
Threat (level 1) | Threat (level 2) | Impact and Stresses | |||||||
---|---|---|---|---|---|---|---|---|---|
Agriculture & aquaculture | Annual & perennial non-timber crops - Agro-industry farming | Timing | Scope | Severity | Impact | ||||
Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
Agriculture & aquaculture | Wood & pulp plantations - Agro-industry plantations | Timing | Scope | Severity | Impact | ||||
Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
Biological resource use | Hunting & trapping terrestrial animals - Intentional use (species is the target) | Timing | Scope | Severity | Impact | ||||
Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
Biological resource use | Hunting & trapping terrestrial animals - Unintentional effects (species is not the target) | Timing | Scope | Severity | Impact | ||||
Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
Biological resource use | Logging & wood harvesting - Unintentional effects: (large scale) [harvest] | Timing | Scope | Severity | Impact | ||||
Ongoing | Minority (<50%) | Slow, Significant Declines | Low Impact: 5 | ||||||
|
|||||||||
Biological resource use | Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest] | Timing | Scope | Severity | Impact | ||||
Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
Residential & commercial development | Housing & urban areas | Timing | Scope | Severity | Impact | ||||
Ongoing | Minority (<50%) | Slow, Significant Declines | Low Impact: 5 | ||||||
|
Purpose | Scale |
---|---|
Food - human | subsistence, national |
Medicine - human & veterinary | subsistence, national |
Pets/display animals, horticulture | international |
Recommended citation
BirdLife International (2024) Species factsheet: Great Hornbill Buceros bicornis. Downloaded from
https://datazone.birdlife.org/species/factsheet/great-hornbill-buceros-bicornis on 23/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 23/12/2024.